Phone numbers in Sterling, Illinois
Sterling has 21 phone prefixes in area codes 779, 815.
Biggest holders: AT&T (local phone), T-Mobile (including Sprint), UScellular. This is the local calling area (rate center) where those prefixes were first assigned.
- Mobile carrier 38%
- Local phone company 38%
- Internet / business phone carrier 14%
- Phone company 10%
Every prefix in Sterling
Search the first six digits of a number in this list. If it's here, the number started in Sterling with the carrier shown. If it isn't, check the Illinois page or look the number up.
| Prefix | Carrier | Type | Assigned |
|---|---|---|---|
| 779-245 | T-Mobile (including Sprint) | Mobile carrier | 2008 |
| 779-250 | T-Mobile (including Sprint) | Mobile carrier | 2018 |
| 779-297 | IP Horizon | Internet / business phone carrier | 2020 |
| 779-430 | Wavenation | Phone company | 2025 |
| 779-587 | Ahoi | Phone company | 2026 |
| 779-790 | Commio | Internet / business phone carrier | 2023 |
| 815-213 | UScellular | Mobile carrier | 2004 |
| 815-380 | Level 3 (Lumen) | Internet / business phone carrier | – |
| 815-441 | Verizon Wireless | Mobile carrier | – |
| 815-499 | UScellular | Mobile carrier | – |
| 815-535 | AT&T (local phone) | Local phone company | – |
| 815-548 | AT&T (local phone) | Local phone company | – |
| 815-564 | AT&T (local phone) | Local phone company | – |
| 815-590 | T-Mobile (including Sprint) | Mobile carrier | 2003 |
| 815-622 | AT&T (local phone) | Local phone company | – |
| 815-625 | AT&T (local phone) | Local phone company | – |
| 815-626 | AT&T (local phone) | Local phone company | – |
| 815-631 | AT&T (local phone) | Local phone company | – |
| 815-632 | AT&T (local phone) | Local phone company | – |
| 815-716 | MetroPCS (T-Mobile) | Mobile carrier | 2001 |
| 815-718 | UScellular | Mobile carrier | 2002 |
Most prefixes are pooled: the 10,000 numbers in each are handed out in blocks of 1,000 to different carriers, and people can also take their numbers to another carrier. So the carrier shown is where the prefix started, not a guarantee about any one number. Source: NANPA central office code records, 2026-10-10.